The invention relates to a device for controlling the flow of a liquid or gaseous medium.
A known device for controlling the flow of a liquid or gaseous medium (EP 1 536 169 A1) includes a 2/2 directional control valve having a valve element that controls a valve opening through which the medium can flow, and an electromagnet that actuates the valve element. The valve element is disposed in a valve chamber formed in a valve housing; the valve opening, which is situated between a valve inlet and a valve outlet, is formed in the valve chamber. The valve opening is enclosed by a valve seat with which the valve element interacts to close and open the valve opening. The electromagnet includes a magnetic circuit having a solenoid coil or excitation coil, an armature sleeve that accommodates the solenoid coil on the outside and is closed by an armature plug, and a solenoid armature that is guided in the interior of the armature sleeve.
The solenoid armature is held, in an axially displaceable manner, in the armature sleeve using two flat springs disposed on the upper and lower end faces; together with the armature plug, the solenoid armature limits a working air gap contained in the magnetic circuit. The armature sleeve protrudes into the valve chamber. The point of entry is sealed against the valve housing by a sealing ring. The valve element includes a sealing holder having a plug, which is inserted axially into the solenoid armature, and a sealing plate that is accommodated in the sealing holder and interacts with the valve seat. The closed state of the valve is brought about by a valve closing spring that acts on the solenoid armature; the valve closing spring is disposed in a blind hole in the solenoid armature, bears against the armature plug, and presses the sealing plate against the valve seat.
When current is supplied to the electromagnet, the solenoid armature is displaced axially against the spring force of the valve closing spring, and the solenoid armature lifts the valve element off of the valve seat, thereby opening the valve opening and, depending on the lift of the valve element, a larger or smaller volume of medium flows from the valve inlet via the valve chamber to the valve outlet. The valve chamber is filled continually with medium, and so the medium constantly flows around the valve element and the end face of the solenoid armature.